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arm64/mm: Refactor __do_page_fault()

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__do_page_fault() is over complicated with multiple goto statements. This
cleans up the code flow and while there drops local variable vm_fault_t.

Reviewed-by: Mark Rutland <Mark.rutland@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Anshuman Khandual 2019-06-07 14:43:06 +05:30 committed by Catalin Marinas
parent c49bd02f4c
commit 4745224b45
1 changed files with 11 additions and 19 deletions

30
arch/arm64/mm/fault.c

@ -397,37 +397,29 @@ static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *re
static vm_fault_t __do_page_fault(struct mm_struct *mm, unsigned long addr,
unsigned int mm_flags, unsigned long vm_flags)
{
struct vm_area_struct *vma;
vm_fault_t fault;
struct vm_area_struct *vma = find_vma(mm, addr);
vma = find_vma(mm, addr);
fault = VM_FAULT_BADMAP;
if (unlikely(!vma))
goto out;
if (unlikely(vma->vm_start > addr))
goto check_stack;
return VM_FAULT_BADMAP;
/*
* Ok, we have a good vm_area for this memory access, so we can handle
* it.
*/
good_area:
if (unlikely(vma->vm_start > addr)) {
if (!(vma->vm_flags & VM_GROWSDOWN))
return VM_FAULT_BADMAP;
if (expand_stack(vma, addr))
return VM_FAULT_BADMAP;
}
/*
* Check that the permissions on the VMA allow for the fault which
* occurred.
*/
if (!(vma->vm_flags & vm_flags)) {
fault = VM_FAULT_BADACCESS;
goto out;
}
if (!(vma->vm_flags & vm_flags))
return VM_FAULT_BADACCESS;
return handle_mm_fault(vma, addr & PAGE_MASK, mm_flags);
check_stack:
if (vma->vm_flags & VM_GROWSDOWN && !expand_stack(vma, addr))
goto good_area;
out:
return fault;
}
static bool is_el0_instruction_abort(unsigned int esr)